Wireless data and energy transmission device

ABSTRACT

The invention relates to a device for the wireless transmission of data and energy between an element to be mounted on or in a vehicle body, especially a vehicle sliding door ( 2 ), a vehicle seat or a comparable additional unit, and a vehicle body ( 1 ). The basic design of the inventive device comprises an electric power source ( 18 ), control electronics ( 17, 17 ′) mounted in the vehicle body and at least one pertaining coil ( 20 ) also mounted in the vehicle body. The device further comprises control electronics ( 11 ) mounted in the element and at least one pertaining coil ( 19 ) also mounted in the element. Both coils ( 19, 20 ) are inductively coupled via a common transmitting/receiving path to transmit data and energy. According to the invention, the coil ( 19 ) mounted in the element is enclosed by the coil ( 20 ) mounted in the vehicle body and can be displaced in a longitudinal direction within the coil ( 20 ) mounted in the vehicle body or vice versa.

The invention relates to an apparatus for the wireless transmission ofdata and energy between a part, for instance a motor-vehicle slidingdoor, a passenger seat, or a similar part, and a motor-vehicle bodyhaving an electrical power supply, and a body-mounted electroniccontroller having a body-mounted coil, and a part-mounted electroniccontroller having at least one respective part-mounted coil, both coilsbeing inductively coupled to transmit data as well as energy over acommon send/receive path.

Such an apparatus is described in EP 0,616,924. Here there is atransformer that moves energy in one direction and data in bothdirections. Switches on both sides of the transformer serve to monitorhow the transfer is going as well as to evaluate and control it. Inparticular the transformer has a primary and a secondary winding withone of the windings being fixed while the other winding can moverelative to it. The stationary winding is fixed adjacent the steeringcolumn of a motor vehicle while the movable coil is connected with themotor-vehicle steering wheel.

In addition parts such as a sliding door built into or onto amotor-vehicle body are know basically from German 197 17 490. Here anelectrical supply cable is wound up on a drum with a rewinder. The oneend of the supply cable is fixed at the core of the drum of thebody-mounted cable drum and the other end is connected to the slidingdoor. Such connection devices are effective but have a limited servicelife and thus wear out so they must periodically be serviced.

In contrast to the standard personal-use motor vehicles, larger vehiclessuch as so-called minivans or full-size vans or sport-utility vehicleshave in recent years taken up more of the market. Such vehicles areusually provided with at least one motor-vehicle sliding door or doorsthat are usually arranged on the passenger side behind thepassenger-side front door. In order to park in ever smaller spaces suchuse of sliding doors is likely to be found even in other vehicles.Sliding doors can be opened in relatively cramped surroundings and makeit easier to get in or out or load or unload through the substantiallywide open space left by the open sliding door, but are quite a bit moreexpensive compared to the standard hinge-mounted swinging door.

Like swinging doors, sliding doors are often provided with variouselectrical devices as for example an active door-blocked detectingdevice, a door latch with electrical opening or power assist, as well ascentral locking systems and security devices with diagnosable two-waycommunications, an electrical window opener as well as monitoringdevices, e.g. for the window opener and the door latch. In addition itis necessary to transmit electrical energy to power the various devicesand control data to the electronic controllers in the (sliding) door,which is more expensive to do in a sliding door due to the nonfixedcontact than in a swinging door.

It is also known from German 197 06 393 to transmit data in a motorvehicle between a body-mounted electronic controller and a door-mountedelectronic controller in a wireless manner via a transmitter and areceiver communicating via HF or by sound or infrared light.

In this system the energy supply for the electronic controllers in thesliding door when it is open is constituted by a battery that ifnecessary can also be fed by a solar panel. When the door is closed theenergy supply for the door-mounted electronic controller is taken overby the vehicle-mounted battery via a contact system, preferably amultiple-pole plug and socket.

Japanese patent 07-267,020 describes how the electrical supply fordevices in the sliding door take place over a plug/socket system, theplug and socket being in contact with each other when the door is closedto transmit electrical energy to the devices.

The system of German 198 14 670 has a motor-vehicle sliding doorprovided with a battery for its electronic controller that is connectedby a plug/socket arrangement when the door is closed for chargingpurposes.

Finally German 196 02 316 describes an apparatus for transmitting dataor energy. It has an antenna tuned circuit that is made to oscillate bya trigger signal. The oscillations are transferred to a transpondertuned circuit.

Such data and energy transmission and supply systems for electroniccontrollers are generally acceptable. There is however the problem thata plug/socket system exposes the contacts to the air when the door isopened so they can corrode or so that can actually meet physical harm.In this manner the connection for transmitting the small (signal)currents (of about 10 mA and less) for example can lead to problemsbecause of the high resistance.

The use of a separate battery in the (sliding) door to supply current tothe electronic controller requires regular maintenance to ensure thatthe energy supply continues to function. The invention proposes hereto asolution.

It is a technical object of the invention, to so improve such anapparatus that overall one gets a cost-effective, robust, and generallyapplicable transmission of energy and data.

This object is attained according to the invention by an apparatus ofthis type wherein the part-mounted coil is surrounded by thebody-mounted coil and is longitudinally slidable inside the body-mountedcoil or vice versa. In other words, the invention of course encompassesthe reverse system whereby the body-mounted coil is surrounded thepart-mounted coil and is longitudinally slidable inside the part-mountedcoil.

Preferably the body-mounted coil and the part-mounted coil extendgenerally parallel to each other for inductive coupling or haveoverlapping portions. It is only necessary that the inductive couplingbe maintained with the produced electromagnetic fields overlap.

Thus the body-mounted coil is connected both to the electrical powersupply as well as to the electronic controller. The part-mounted coil onthe other hand is connected with the respective electronic controller aswell as with a load.

In this manner the above-detailed contact problem is cured becausewire-connected data and/or energy transmission is done away with. Inaddition the problems of the known roll-up mechanism (see German 197 17490) are no longer to be feared because there is none. The same is truefor a prior-art battery in the sliding door since so that theinstallation and maintenance costs for it are spared. Even safety isimproved because the charge state of this battery does not need to bemonitored. In accordance with the invention the send/receive path canalso be used only for transmitting data or energy for the part orsliding-door electronics.

Contrary to the teachings of EP 0,640,734 there is wireless transmissionof energy and data between individual body parts and not between a keyand the door latch. The same is true with reference to German 196 02316.

It should be emphasized that the described body and part according tothe invention could also be a seat or similar part such as a child seat.In a passenger seat the described system insures that person-specificdata is transmitted without wires from the body-mounted electroniccontroller. This person-specific data is generally provided when adialog between a (HF remote) key and a body-mounted electroniccontroller is established. This is generally initiated by a userinserting the right key peg in an ignition switch on the dashboard afterpositively interrogating and identifying the key type.

In this manner all user- or person-specific data can be transmitted bythe key to the body-mounted electronic controller which at its endhandles the appropriate loads or parts built onto or into the vehicle.This could include for example the desired outside mirror setting, thepositioning of the seat and seat back, and if necessary the illuminationand dashboard lighting. To this end the data and/or energy supply areset up as described above.

Thus the invention makes it possible to supply built on systems, forexample a removable child seat with data and/or energy. It is possibleto identify such a child seat when installed in a passenger seat andturn off the respective air bag so that in case it operates a child inthe child seat is not injured. It is also possible to create a dataand/or energy exchange between the body-mounted electronic controllerand the add-on part, here the child seat. It is possible simply todetermine if a (removable) seat or child seat is present.

It is further within the scope of the invention to establish such asend/receive path between a nonremovable body-mounted base part of avehicle radio and a removable part of the radio. In this manner theuniversal character of the described system for data and/or energytransmission is clear.

This also makes an example clear whereby in a mobile home serving asbody a satellite key is supplied in the described manner with dataand/or energy. Typical uses are still to be seen so that doors, inparticular sliding doors, can in this manner be supplied with energyand/or data.

Further features important to the invention are described in thefollowing. Thus the invention suggests that the body-mounted coil is anair or ferrite coil with an elongated rectangular section and anenclosed longitudinal space for the part-mounted coil slidable therein.Normally this body-mounted coil is mounted in already provided guiderail for the sliding door or is mounted immediately adjacent this guiderail.

Here it is important that the body-mounted coil be insulated from thenormally metallic body. It is further recommended that the part-mountedcoil be arranged in or on a guide slide for guiding the sliding door inthe guide rail. This uses already provided elements of a sliding door,namely a guide rail on one side and on the other side the guide slide.They must only be modified to comply with the invention by beingprovided with the claimed coils. As a result this is a particularlyrobust and compact system because on the one hand the guide rail and onthe other hand the guide slide can be used to hold and/or protect therespective coils.

In order to insure a particularly good inductive coupling between thebody-mounted coil and the part-mounted coil, it is further suggestedthat the part-mounted coil has a cross-sectional size corresponding to awidth of the longitudinal space. It can form a transponder together withthe electronic unit or microprocessor connected to it. In this case thepreferred coils and electronic circuits form the transponder by means ofwhich there is a preferably bidirectional exchange of data and/orenergy.

The transmission of data and/or energy takes place as follows. To supplyenergy to the sliding-door electronic controller and load thebody-mounted coil or the coil element operates as a transmitting antennaand transfers to the part-mounted coil as a receiver a voltage(preferably with a frequency of 125 kHz or 13.56 MHz). Thus the energytransmission is carried out in pulses in order to minimize the currentload of the entire apparatus. In other words periodic signals with aperiod of preferably 150 ms and a duration of about 5 ms are sent inorder to supply energy to the part-mounted electronic controller or itsload.

In order to facilitate data transfer at the same and/or another time theabove-described pulsating voltage or its signal are modulated. In otherwords the alternating-current portion is modified with a low-frequencyinformation signal which is received in the part-mounted electroniccontroller or its receiver, is filtered, and then demodulated. In anycase the overlain low-frequency information signal can be filtered outand processed in a microprocessor in order to convert the varioussignals into the appropriate actions. This is known per se.

It is also possible in the scope of the invention to work with afrequency of from 13 to 13.56 MHz. This always insure that all possibleinformation can be transmitted from the body to the sliding door or viceversa. Thus for example the following devices built into a sliding doorcan be queried: locking-pawl switch, fork switch, central-lock switch,antitheft-protection switch, child-safety switch, door-blockage switch,position detector for the window lifter, and so on.

Of course in addition to the wireless energy transmission it is possibleto use a hard-wired energy transmission that is particularly useful inthe case that the sliding door is closed. In this case the describeddevices can be connected conventionally, that is via contacts, with thenecessary energy sources on the motor-vehicle body. It is thereforepossible to supply only the electronic controller with energy, while theother devices can be fed with current by a hard-wired connection.

This always insures that the electronic controller and devices mountedon the sliding door (for example a central locking device and/or awindow drive) are supplied with data and energy regardless of the actualposition of the sliding door. In other words according to the inventionthe same status and functioning is achieved as by a pivotal door orhatch that is supplied conventionally by a hard-wired connection withthe necessary data and/or energy. This constitutes a major advantage.

The invention is described more closely in the following with referenceto a drawing showing one embodiment. Therein:

FIG. 1 is a motor vehicle with a partially opened sliding door;

FIG. 2 is a schematic representation of the main parts according to FIG.1 with the door closed;

FIG. 3 shows the main elements of the invention;

FIGS. 4a, 4 b, and 4 c show a first embodiment of the data/energytransmission system with a guide rail of a sliding door in perspectiveview (see FIG. 4a), in schematic top view (see FIG. 4b), and in section(see FIG. 4c);

FIG. 5 is a variant on the structure of FIG. 4; and;

FIG. 6 is a variant in a motor-vehicle seat.

FIG. 1 shows a motor vehicle 1 with a side-mounted door 2. Thismotor-vehicle door 2 is a movable cover and body part forming part ofthe motor-vehicle body, here a motor-vehicle sliding door 2. Thismotor-vehicle sliding door 2 is guided in guide rails 3, 4, and 5.Unillustrated rollers or a guide slide are employed. FIG. 1 shows themotor-vehicle sliding door 2 in a partially open position while FIG. 2shows the closed position. When the motor-vehicle sliding door 2 isshifted into the closed position it moves out of the slide plane.

Movement of the motor-vehicle sliding door 2 can be effected manually orby electric power. To this end there is a drive 6 which in thisembodiment has a toothed belt and a coupling arrangement for closing andopening as described in detail in German patent application 197 02 698.

The drive 6 has a sliding-door actuator 6 a which can be mechanicallycontrolled. In addition FIG. 1 shows a coupling 6 b for theabove-mentioned toothed belt. In this embodiment the sliding-dooractuator 6 a is electronically controlled. In addition FIG. 1 shows atleast one motor-vehicle door latch 7 in the body. This motor-vehicledoor latch 7 has a latch part 7 a on the motor-vehicle door 2 or slidingdoor 2 and a keeper 7 b on the body. The motor-vehicle door latch 7 isalso responsible for the above-mentioned shifting in (when closing) andshifting out (when opening) of the motor-vehicle sliding door 2.

To this end the latch keeper 7 b according to this embodiment is a servokeeper 7 b. FIG. 1 further shows an actuating mechanism B with antitheftprotection as well as a control latch 9 which is mechanically coupledwith an outside door handle 10 (see the dot-dash “mechanical” connectionin FIG. 1). Furthermore there is a mechanical connection between theoutside door handle 10 (or the inside handle), the latch 9, theactuating mechanism 8 with antitheft protection, the latch 7 a of themotor-vehicle door latch 7 (see the mechanical connection from thecontrol latch 9 to the latch 7 a in FIG. 1). A child-safety switch andan also unillustrated central locking system are connected to thecontrol latch 9. Further particulars are described in above cited German197 06 393.

In the motor-vehicle sliding door 2 there is in addition a door-mountedcontroller 11 or electronic controller 11 which is connected with thelatch 7 a. The electronic controller 11 receives signals from alatch-pawl switch 12 as well as from a fork switch 13. In addition anoutside door-actuating device 14 has an active antipinch protectorconstituted as a peripheral electrically conducting plastic profilewhose resistance changes with pressure. The electronic controller 11operates an inside actuating device 15 as well as if necessary alatching pawl 16. Finally according to the signals from the devices 12,13, and 14 the motor-vehicle door 2 can be closed electrically (or alsomechanically) by actuating an inside or outside handle (see FIG. 2).

The body carries an electronic controller 17 as well as a receiver 17′which are together mounted in the C-column of the motor vehicle 1. Inaddition there is an electrical power supply 18 in the motor vehicle 1.Wireless data and/or energy transfer between the motor vehicle 1 or itsbody and built-on parts 2 or the motor-vehicle sliding door 2 is via twocoils 19 and 20 which send and receive inductively. The door-mountedcoil 19 with the controller 11 and, if necessary, any loads such as thelatch pawl 16 or the inside actuating mechanism 15 are thus connected tothe power supply. Data evaluation and transmission are handled by theelectronic controller 11 in the manner described above.

In this embodiment a supplemental energy supply for the loads 15 and 16or 11 can take place via contact pins 21 when the motor-vehicle slidingdoor 2 is closed. This is however not essential because according to theinvention the energy transfer can always be done via the coils 19 and20. The same is true for data transfer which is normally bidirectional.

The body-mounted coil 20 is connected via the receiver 17′ with theelectrical supply 18 and thus to the controller 17. In this embodimentboth coils 19 and 20 have overlapping portions S₁ and S₂ that fittogether or extend parallel to each other as shown in FIG. 3 in order toeffect the necessary transformer-type inductive coupling. This ensuresthat the existing and queried magnetic fields or the respective magneticinductions →B₁ and →B₂ and the respective coil portions S₁ and S₂ oroverlaps are generally parallel to each other (see the illustratedmagnetic field lines in FIG. 2).

In order to ensure the wireless data and/or energy transfer even whenthe motor-vehicle sliding door 2 is moving, the body-mounted coil 20 isintegrated in the guide rail—in this embodiment the upper guide rail3—of the motor vehicle 1. The body-mounted coil 20 extends mainlyhorizontally but can also be vertical or at any desired angle to themovement plane.

The body-mounted coil 20 is an air coil of lacquered copper wire with acoil body holding it in or on the body. This coil or air coil 20 has anelongated rectangular shape S₂ whose longest side generally correspondsto the length of the door opening. The coil 20 encloses a longitudinalspace 22 of generally oval shape which has a width T of between 20 and50 mm, preferably about 18 mm.

The device/part/sliding-door coil 19 is longitudinally slidable in thislongitudinal gap 22. This coil is also for example an air coil withcopper wire on a coil core (preferably of plastic). This coil 19 has ashape S₁ corresponding to the width T of the longitudinal space 22. Itcan be a circular coil with a length between 20 and 60 mm, preferably 40mm. Round as well as rectangular shapes S₁ with rounded corners arepossible. The diameter preferably corresponds to the width T and isabout 10 to 50 mm, preferably 10 to 30 mm. Most preferably the diameteris about 18 mm.

In any case the fit of the portion S1 of the coil 19 in the gap 22 ofwidth T makes for an optimal guiding and bidirectional coupling of thedoor-mounted coil 19 with the body-mounted coil 20 via their electricalfield.

FIG. 3 shows the important parts of the invention in simplified form.FIG. 6 shows a car seat corresponding to FIG. 3. Here the body-mountedcoil 20 is mounted in a floor rail 23 and is inductively coupled to thepart-mounted coil 19. This coil 19 is mounted in unillustrated rollersby means of which the passenger seat is longitudinally slidable in thefloor rail 23. In addition the part-mounted controller 11 is showninside the passenger seat. Here the coupling and shapes of the coils 19and 20 can be like what is shown in below-detailed FIGS. 4 and 5.

FIG. 4a shows a guide rail 3 on the motor-vehicle sliding door 2 whichsimultaneously serves as a coil support and preferably is made ofplastic. This guide rail 3 extends generally in the motor-vehicle traveldirection in the outer skin of the vehicle body as shown clearly in FIG.1. The part- or door-mounted coil is mounted at an end of an outrigger24 carrying the unillustrated motor-vehicle sliding door. This coil 19slides as shown in FIGS. 4b and 4 c along the body-mounted coil 20, thatis both coils 19 and extend generally parallel to each other.

As a result of the very close juxtaposition to each other, the desiredinductive coupling is achieved which makes possible the described dataand/or energy transfer. In the embodiment according to FIG. 4 the coil19 is imbedded in a slide shoe 25 made for example of plastic and whichmoves along the guide rail 3 of metal or plastic and that serves as aguide slide.

The guide rail 3 carries the coil 20 that in the variant of FIG. 5 isembedded in the guide rail 3. According to this variant the coil 19 andthe coil 20 are spaced from each other which is not a problem as long astheir electromagnetic fields overlap, that is the coils 19 and 20 caninduce fields of sufficient strength in each other.

What is claimed is:
 1. An apparatus for the wireless transmission ofdata and energy between a part, for instance a motor-vehicle slidingdoor, a passenger seat, or a similar part, and a motor-vehicle bodyhaving an electrical power supply, and a body-mounted electroniccontroller having a body-mounted coil, and a part-mounted electroniccontroller having at least one respective part-mounted coil, both coilsbeing inductively coupled to transmit data as well as energy over acommon send/receive path, wherein the part-mounted coil is surrounded bythe body-mounted coil and is longitudinally slidable inside thebody-mounted coil or vice versa.
 2. The apparatus according to claim 1wherein the body-mounted coil and the part-mounted coil extend generallyparallel to each other or have overlapping portions.
 3. The apparatusaccording to claim 1 wherein the body-mounted coil is an air or ferritecoil with an elongated rectangular section and an enclosed longitudinalspace for the part-mounted coil slidable therein, or vice versa.
 4. Theapparatus according to claim 3 wherein the part-mounted coil has across-sectional size corresponding to a width of the longitudinal space.5. The apparatus according to claim 1 wherein the part-mounted coiltogether with the electronic unit connected to it form a transponder. 6.The apparatus according to claim 1 wherein the body-mounted coil isbuilt into a guide rail, preferably an upper guide rail for the slidingdoor, and the part-mounted coil is mounted on a guide slide for guidingthe motor-vehicle sliding door in the guide rail.
 7. The apparatusaccording to claim 1 wherein bidirectional data transfer takes place.